Fix IN-DL parser

[yifanmai]

Issue

Closes #6741

Description

Fixes the IN-DL parser:

• This parser contains a constant lookup table of power plant names to plant type. The parser broke because one of the plant names was changed on the scraped HTML page. This updates the plant name in the lookup table to match the HTML page.
• The parser was looking for values under the "Actual" column, but the parser used a hardcoded column index, and the column index changed in the HTML table. This changes the parser to determine the correct column index using the header row.

Preview

$ poetry run test_parser IN-DL
Parser result:
{'datetime': datetime.datetime(2025, 1, 27, 3, 46, 2, tzinfo=zoneinfo.ZoneInfo(key='Asia/Kolkata')),
 'production': {'biomass': 30.0, 'coal': 0.0, 'gas': 40.0},
 'source': 'delhisldc.org',
 'zoneKey': 'IN-DL'}
---------------------
took 1.52s
min returned datetime: 2025-01-26 22:16:02+00:00 UTC
max returned datetime: 2025-01-26 22:16:02+00:00 UTC  -- OK, <2h from now :) (now=2025-01-26T22:16:23+00:00 UTC)

Double check

• I have tested my parser changes locally with poetry run test_parser "zone_key"
• I have run pnpx prettier@2 --write . and poetry run format in the top level directory to format my changes.

[VIKTORVAV99]

LGTM! 🎉